Surgical Management of Valvular Heart Disease in Mucopolysaccharidoses: A Review of Literature.

Mucopolysaccharidoses are extremely rare diseases that are frequently presenting with structural heart problems of the aortic and mitral valve in combination with myocardial dysfunction. In a substantial proportion, this leads to heart failure and is a leading cause of death in these patients. As this glycosaminoglycan degradation defect is associated with other conditions strongly influencing the perioperative risk and choice of surgical technique, multidisciplinary planning is crucial to improve short- and long-term outcomes. The extensive variance in clinical presentation between different impaired enzymes, and further within subgroups, calls for personalised treatment plans. Enzyme replacement therapies and bone marrow transplantation carry great potential as they may significantly abrogate the progress of the disease and as such reduce the clinical burden and improve life expectancy. Nevertheless, structural heart interventions may be required. We reviewed the existing literature of the less than 50 published cases regarding surgical management, technique, and choice of prostheses. Although improvement in therapy has shown promising results in protecting valvar tissue when initiated in infancy, concerns regarding stability of this effect and durability of biological prostheses remain.

The fate of patients with acute aortic syndrome during the coronavirus (COVID-19) pandemic: A UK multicenter study.

OBJECTIVE: The coronavirus disease 2019 (COVID-19) pandemic has posed challenges to health care services across the world. There has been a significant restructuring of health care resources to protect services for patients with COVID-19-related illness and to maintain emergency and urgent medical and surgical activity. This study assessed access to emergency treatment, logistical challenges, and outcomes of patients with acute aortic syndrome during the early months of the COVID-19 pandemic in the United Kingdom. METHODS: This was a multicenter study, from March 1 to May 20, 2020 that included 19 cardiac centers, was a retrospective analysis of prospectively collected data obtained from individual centers' national cardiac surgical databases. Demographic details, choice of treatment, operative details, and outcomes were collected. COVID-19 screening, timing of surgery, and outcomes of COVID-19-positive and -negative patients were also analyzed. RESULTS: In total, 88 patients presented with acute aortic syndrome to participating centers from March 1 to May 20, 2020. There were 79 aortic dissections (89.8%), 7 intramural hematomas (7.9%), and 2 penetrating aortic ulcers (2.3%). Seventy-nine patients (89.8%) underwent surgery. In-hospital mortality was 25.3% (n = 20). Postoperative complications included 13.9% postoperative stroke (11.4% permanent and 2.3% temporary), 16.5% rate of hemofiltration, and 10.1% rate of tracheostomy. Nine patients were treated conservatively with a mortality of 60%. Seven patients were diagnosed with COVID-19, and there was no associated mortality. CONCLUSIONS: Despite extensive restructuring of health care resources, access to emergency and urgent treatment for patients with acute aortic syndrome was maintained in the early months of the COVID-19 pandemic in the United Kingdom. Clinical outcomes were similar to the prepandemic period.

Early experience of aortic surgery during the COVID-19 pandemic in the UK: A multicentre study.

BACKGROUND: A significant restructuring of the healthcare services has taken place since the declaration of the coronavirus disease 2019 (COVID-19) pandemic, with elective surgery put on hold to concentrate intensive care resources to treat COVID-19 as well as to protect patients who are waiting for relatively low risk surgery from exposure to potentially infected hospital environment. METHODS: Multicentre study, with 19 participating centers, to define the impact of the pandemic on the provision of aortovascular services and patients' outcomes after having adapted the thresholds for intervention to guarantee access to treatment for emergency and urgent conditions. Retrospective analysis of prospectively collected data, including all patients with aortovascular conditions admitted for surgical or conservative treatment from the 1st March to the 20th May 2020. RESULTS: A total of 189 patients were analyzed, and 182 underwent surgery. Diagnosis included: aneurysm (45%), acute aortic syndrome (44%), pseudoaneurysm (4%), aortic valve endocarditis (4%), and other (3%). Timing for surgery was: emergency (40%), urgent (34%), or elective (26%). In-hospital mortality was 12%. Thirteen patients were diagnosed with COVID-19 during the peri-operative period, and this subgroup was not associated with a higher mortality. CONCLUSIONS: There was a significant change in service provision for aortovascular patients in the UK. Although the emergency and urgent surgical activity were maintained, elective treatment was minimal during early months of the pandemic. The preoperative COVID-19 screening protocol, combined with self-isolation and shielding, contributed to the low incidence of COVID-19 in our series and a mortality similar to that of pre-pandemic outcomes.

Do surgical modifications at the annular level during the Ross procedure negatively influence the structural and functional durability of the autograft?

OBJECTIVES: Do surgical modifications at the annular level (e.g. the modified Ross-Konno procedure or reduction plasty) influence the structure and function of the Ross autograft at the mid-term follow-up? METHODS: From June 2001 to July 2009, 49 patients (37 men and 12 women), mean age 10.5 ± 5.7 years (range 2 weeks to 17.8 years), underwent Ross operations. Twenty-one patients underwent additional aortic annulus reduction plasty and 9 patients a modified Ross-Konno procedure. The need for reintervention, reoperation and valve function were retrospectively analysed for a mean follow-up of 4.6 ± 2.7 years (range 9 days to 9.2 years). RESULTS: There were no intraoperative or early death. Three late deaths occurred. Survival at 4 years was 91.9 ± 4.6%. In the overall cohort, aortic annular growth was 1 mm/year, corresponding to a z-score increase of 0.24/year (no mismatch group), 0.21/year (reduction plasty group) and 0.34/year (Ross-Konno group). At the last follow-up, sinotubular junction z-scores were 2.8 ± 1, 3 ± 1 and 2.4 ± 0.9 in the no mismatch, reduction plasty, and Ross-Konno groups, respectively. Ninety-three percent of patients presented with none-to-mild autograft valve regurgitation. The Ross-Konno group showed a significant increase in aortic annulus size (z-score of the annulus at the last follow-up 3.6 ± 1.6; P = 0.036). The no mismatch and the reduction plasty groups showed z-scores within the normal range (2.1 ± 1.7 and 2.5 ± 1.6, respectively). CONCLUSIONS: Additional aortic annulus reduction or enlargement does not disturb the structural and functional durability of the autograft at the mid-term follow-up. Long-term autograft integrity, especially in the Ross-Konno group, remains to be investigated.

Moderate hypothermia during ex vivo machine perfusion promotes recovery of hearts donated after cardiocirculatory death†.

OBJECTIVES: To establish the optimal machine perfusion temperature for recovery of hearts in a rodent model of donation after declaration of cardiocirculatory death (DCD). METHODS: Hearts from male Lewis rats (n = 14/group) were subjected to 25 min of in situ warm (37°C) ischaemia to simulate DCD. They were then explanted and reperfused with diluted autologous blood for 60 min at 20, 25, 30, 33 or 37°C, after which they were stored at 0-4°C in Custodiol preservation solution for 240 min. Fresh-excised and cold-stored ischaemic hearts were used as controls. The viability of the different groups was assessed by comparing heart rate and left ventricular contractility in a Langendorff circuit, as well as perfusate levels of troponin-t and creatine kinase (CK), and myocardial levels of adenosine triphosphate (ATP) and reduced glutathione. RESULTS: During ex vivo reperfusion, hearts in all groups resumed beating within minutes. The mean heart rate was highest in the 37°C group at 154.72 ± 33.01 beats × min(-1) (bpm), and declined in proportion to temperature to 39.72 ± 5.53 bpm at 20°C. Troponin-t levels were highest in the 37°C group (79.49 ± 20.79 µg/l), the values were significantly lower in all other reconditioned groups with a minimum of 12.472 ± 7.08 µg/l in the 20°C group (P < 0.0001). Tissue ATP levels ranged from 4.32 ± 1.71 µmol/g at 33°C to 4.59 ± 1.41 µmol/g at 30°C, all significantly higher than the mean ATP level of 1.41 ± 0.93 µmol/g in untreated ischaemic hearts (P < 0.0001). During Langendorff assessment, the mean heart rate and contractility of all groups were higher than those of cold-stored ischaemic hearts (P < 0.0001), yet not significantly different from those of fresh controls. The perfusate levels of troponin-t and CK, and myocardial levels of reduced-glutathione and ATP were not significantly different between groups. CONCLUSION: Our results suggest that mild hypothermia during ex vivo reperfusion improves recovery of ischaemic hearts in a rodent DCD model.

Recovery of donor hearts after circulatory death with normothermic extracorporeal machine perfusion.

OBJECTIVES: A severe donor organ shortage leads to the death of a substantial number of patients who are listed for transplantation. The use of hearts from donors after circulatory death could significantly expand the donor organ pool, but due to concerns about their viability, these are currently not used for transplantation. We propose short-term ex vivo normothermic machine perfusion (MP) to improve the viability of these ischaemic donor hearts. METHODS: Hearts from male Lewis rats were subjected to 25 min of global in situ warm ischaemia (WI) (37°C), explanted, reconditioned for 60 min with normothermic (37°C) MP with diluted autologous blood and then stored for 4 h at 0-4°C in Custodiol cold preservation solution. Fresh and ischaemic hearts stored for 4 h in Custodiol were used as controls. Graft function was assessed in a blood-perfused Langendorff circuit. RESULTS: During reconditioning, both the electrical activity and contractility of the ischaemic hearts recovered rapidly. Throughout the Langendorff reperfusion, the reconditioned ischaemic hearts had a higher average heart rate and better contractility compared with untreated ischaemic controls. Moreover, the reconditioned ischaemic hearts had higher tissue adenosine triphosphate levels and a trend towards improved tissue redox state. Perfusate levels of troponin T, creatine kinase and lactate dehydrogenase were not significantly lower than those of untreated ischaemic controls. The micro- and macroscopic appearance of the reconditioned ischaemic hearts were improved compared with ischaemic controls, but in both groups myocardial damage and oedema were evident. CONCLUSIONS: Our results indicate that functional recovery from global WI is possible during short-term ex vivo reperfusion, allowing subsequent cold storage without compromising organ viability. We expect that once refined and validated, this approach may enable safe transplantation of hearts obtained from donation after circulatory death.

Hybrid approach for hypoplastic left heart syndrome and its variants: the fate of the pulmonary arteries.

OBJECTIVES: To analyse the results of hybrid palliation of hypoplastic left heart syndrome (HLHS) patients and its variants with an emphasis on the long-term fate of the pulmonary arteries. METHODS: We analysed 28 neonates (2006-11) with HLHS and its variants, who underwent bilateral pulmonary artery banding, patent ductus arteriosus (PDA) stenting and balloon atrial septostomy using a true hybrid approach. Median age and weight were 4 (0-36) days and 3 (1.9-3.7) kg respectively. Diagnoses included 23 HLHS and 5 variants. The fate of all surviving branch pulmonary arteries (PA) after a hybrid approach were compared with their counterparts in 29 Norwood I survivors (2002-11). RESULTS: Four of 28 hybrid procedures needed to be converted to a Norwood procedure. Mortality after stage I hybrid palliation was 3/24 (12.5%). All 21 acute survivors underwent a comprehensive stage II at a median age of 4 (2.3-5.7) months, without any mortality (0%). Eleven of 21 comprehensive stage II survivors have undergone extracardiac Fontan; including 1 who underwent a rescue Fontan at 7 months of age and died (1/11: 9%). While 18/21 (86%) needed branch PA intervention in the hybrid group during the median follow-up duration of 39 (10-81) months, 9/29 (31%) needed the same in the Norwood group during a median follow-up duration of 58 (16-128) months (P < 0.001). Eight of 21 (38%) needed stenting [all on the left pulmonary artery (LPA)] in the hybrid group vs 5/29 (17%) in the Norwood group (P = 0.097). Ten of 21 (48%) patients had surgical/catheter intervention on both branch PA in the hybrid group vs 2/29 (7%) in the Norwood group (P = 0.001). Pre-Fontan Nakata index was significantly better in the Norwood group 206 (118-406) compared with the hybrid group 153 (56-230) mm(2)/m(2) (P = 0.01). The comparable lower lobe indices were 149 (103-333) and 137 (45-178) mm(2)/m(2) (P = 0.04), respectively. CONCLUSIONS: Hybrid approach can be pursued with a low mortality. However, the high frequency of catheter and/or surgical interventions, and the sluggish growth of the branch PA pre-Fontan need innovative solutions. A comparison of the neurodevelopmental outcome for the hybrid vs the Norwood cohort would define the role of the hybrid strategy in the treatment of HLHS and its variants.

Pediatric coronary artery revascularization: a European multicenter study.

BACKGROUND: We sought to evaluate the hospital and midterm results of different surgical revascularization techniques in pediatric patients within the European Congenital Heart Surgeons Association. METHODS: From 1973 to 2011, 80 patients from 13 European Congenital Heart Surgeons Association centers underwent 65 pediatric coronary artery bypass grafting (PCABG) and 27 other coronary artery procedures (OCAP; 12 patients had combined PCABG and other coronary artery procedures). Excluded were patients with Kawasaki disease. Median age at the time of coronary procedure was 2.3 years (range, 2 days to 16.9 years); 33 patients (41.2%) were younger then 12 months. An emergency procedure was necessary in 34 patients (42.5%). RESULTS: Twelve patients (15%) died in the hospital; age at surgery (p=0.02) and the need for an emergent procedure (p=0.0004) were related to hospital mortality. Median follow-up time was 7.6 years (range, 0.9 to 23 years). There were 3 late cardiac deaths, all after a median time of 4 years (range, 9 months to 8.8 years) after PCABG. Fourteen patients (20.5%) presented with symptoms, including congestive heart failure (n=10) and angina (n=4), that were significantly associated with a low ejection fraction (p<0.001) and the presence of moderate or severe mitral valve regurgitation (p=0.0003). Six patients underwent a reintervention for impaired myocardial perfusion; all of them had a stenotic or atretic PCABG (p=0.001), and the majority were symptomatic (5 of 6 patients; 83.3%; p=0.001). CONCLUSIONS: Both PCABG and other coronary artery procedures are suitable surgical options in pediatric patients with impaired myocardial perfusion, which increases operative and midterm survival. Such population of patients needs to be followed for life to prevent and treat any possible cause of further myocardial ischemia.

Recycling of the pulmonary valve: an elegant solution for secondary pulmonary regurgitation in patients with tetralogy of Fallot.

BACKGROUND: The purpose of this study was to review our experience with recycling of the pulmonary valve in cases of chronic pulmonary insufficiency after a transannular patch procedure as part of a repair of tetralogy of Fallot. METHODS: Eight patients in whom the technique was used were reviewed. Technically, the valve was reapproximated at the anterior commissure if the valve leaflet was sufficiently developed and of good tissue quality. Additional corrections were performed in 5 patients (resection of an infundibular aneurysm [5 patients], repair of the tricuspid valve [1 patient]). RESULTS: The valve was competent with no or trivial regurgitation in 5 patients and a small regurgitation in 3 patients. There was no significant transvalvular gradient in 5 patients with tricuspid valves and a small gradient in 3 patients with a bicuspid valves (<23 mm Hg). The valve function remained stable over the follow-up period (median time, 32 months). CONCLUSIONS: Recycling of the pulmonary valve is an interesting concept that could avoid the necessary reoperations linked with valves or valved prostheses. The repair must be carefully followed in bicuspid valves because of a reduction in the opening area. Valve leaflets of good quality should be preserved during the primary repair of tetralogy of Fallot and the transannular incision should be made across the anterior commissure if possible. These steps should allow a few patients to profit from a recycling of their valves in the future.

Aortic arch enlargement and coarctation repair through a left thoracotomy: significance of ductal perfusion.

OBJECTIVE: To analyse the technique of neonatal aortic arch enlargement without cardiopulmonary bypass through a left posterior thoracotomy, as an adjunct to extended resection for Coarctation and severe arch hypoplasia. METHODS: Ten neonates with coarctation, severe arch hypoplasia and a persistent ductus arteriosus (PDA) were subjected to arch repair through a left posterior thoracotomy. Nine of these patients had associated significant intracardiac anomalies; three of them received pulmonary artery (PA) banding. After exclusion from circulation, the roof of the intervening arch between left carotid and left subclavian was enlarged using a patch. After adequate reperfusion, a classic resection and extended end-to-end anastomosis was performed. Median age and weight were 5.5 (1-10) days and 3.3 (2.2-4.1) kg respectively. The median preoperative arch diameter was 1.07 (0.75-1.32) mm/kg body weight. RESULTS: All patients could be successfully operated with this approach. The non-ischaemic and ischaemic aortic clamp times were 40 (15-68) and 23 (18-32) min, respectively. The median postoperative arch diameter achieved was 1.43 (1.06-1.46) mm/kg body weight. None of the patients had significant gradient early postoperatively. Two patients with recurrent stenosis were successfully treated with balloon dilatation (1) or surgery with cardiopulmonary bypass (CPB) (1). One patient has a corrected gradient of 16 mmHg in the proximal arch which is being observed. The remaining patients are free from stenosis at a median follow-up of 30.1 (13.2-57.8) months. CONCLUSIONS: Use of PDA for lower body perfusion allows complex reconstruction of the arch without incurring lower body ischaemia. The extended resection could then be performed without excessive stretch. This modification saves these patients from undergoing a complex arch reconstruction with CPB in the early neonatal period.